Full moon has no effect on mental health

London: Contrary to popular belief, the full moon does not increase the incidence of psychological problems, researchers have revealed.A team of researchers directed by Professor Genevieve Belleville of Universite Laval's School of Psychology examined the relationship between the moon's phases and the number of patients who show up at hospital emergency rooms experiencing psychological problems.

To determine whether the widespread belief linking the moon to mental health problems was true, researchers evaluated patients who visited emergency rooms at Montreal's Sacre-Coeur Hospital and Hotel-Dieu de Levis between March 2005 and April 2008.

They focused specifically on 771 individuals who showed up at the emergency room with chest pains for which no medical cause could be determined.

Psychological evaluations revealed that a sizeable number of these patients suffered from panic attacks, anxiety and mood disorders, or suicidal thoughts.

Using lunar calendars, the researchers determined the moon phase in which each of these visits occurred.The results of their analyses revealed no link between the incidence of psychological problems and the four lunar phases.

There was one exception, however; anxiety disorders were 32 per cent less frequent during the last lunar quarter.

"This may be coincidental or due to factors we did not take into account," Belleville said."But one thing is certain: we observed no full-moon or new-moon effect on psychological problems," she said.The study's conclusions run contrary to what many believe, including 80 per cent of nurses and 64 per cent of doctors who are convinced that the lunar cycle affects patients' mental health.

"Otherwise, this misperception could, on the one hand, color their judgment during the full moon phase; or, on the other hand, make them less attentive to psychological problems that surface during the remainder of the month," she added.

The study is published on the website of the scientific journal General Hospital Psychiatry.